The increased availability and use of drugs of abuse by the general population has caused employers, governmental agencies, sports groups and other organizations to utilize drug screening both as a condition of employment and in order to maintain safety in the work-place. Typical drug screening tests are performed for the purpose of quickly identifying on a qualitative basis the presence of drugs in a body fluid which may be urine. A complete analysis of the sample might then be carried out in a laboratory in the event that the preliminary screening results are positive. More and more such drug screenings are taking place on site or the workplace and are generally carried out by testing personnel who may have only limited technical training. It is thus important that the drug screening procedure is simple to perform but yield reliable results. Further, the test device must be such so as to enable the testing personnel to avoid any contact with the fluid specimen which is being tested.
Various forms of devices which have been proposed for the collection and taking of body fluids, such as urine, have proved to be cumbersome in operation since they involve a number of separate steps. Initially, the sample was collected and several additional steps were then required to transfer the urine sample to an analysis device. This multiple step procedure required the manual handling of the specimen through various devices and the use of such transfer devices inevitably caused spills which may result in contamination to the tester and surroundings. In addition, non technical personnel who perform the screening tests on urine samples objected to coming into any kind of contact with the urine sample and even the handling of the sample itself.
Another form of a testing device required the transfer of the specimen or at least a portion thereof, to another compartment of the collection container in order to perform the test This transfer of the specimen required vigorious shaking of the container or turning the container upside down in order to cause the flow of the specimen into a test compartment. It was therefore necessary to make the containers leak proof under such conditions and the result was a complicated and expensive container structure.
The testing device also included a screen test card for drugs of abuse which comprised a thin flat member having a plurality of immunoassay test strips fastened side by side in parallel on at least one side of the test card. Each test strip is reactive to provide a visual indication in response to a particular drug of abuse.
The test card was insertable into a cup-like container so as to have one end immersed in a urine sample retained in the container to a predetermined depth whereby the visual results of each test strip could be seen through a transparent wall of the container or above the container without removing the test card from the container. The test card thus provides for the simultaneous detection of multiple analytes. If the sample should test “positive” to indicate the presence of a drug in the urine, it is necessary to send the sample to a certified laboratory for confirmatory testing.
Another form of a prior art assay device is disclosed in U.S. Pat. Nos. 6,379,620 and 6,497,843. This form of assay device includes a container for a liquid sample and an assay assembly within the container. The assay assembly has test or assay strips mounted to contact a wicking material which contacts the liquid sample and serves as a path for the liquid sample to react with chemical agents on the strips to give positive, negative or inclusive results.
However, such an assay device requires a precise relationship between the several components of the assay assembly in order that the assay device functions in the manner intended. This necessary relationship was difficult to obtain during the manufacture of the components of the assay assembly and their subsequent assembly within the container.